Apple Inc. is tight-lipped on its upcoming flagship smartphone, iPhone 6, but speculations on its release date and specifications keep surfacing. Now, the latest we heard is that the device will be thinner than Galaxy S5, HTC One M8 and iPhone 5S.

The leaf on the Apple symbol is tinted green at the Apple flagship store on 5th Ave in New YorkREUTERS

Apple Inc. is tight-lipped on its upcoming flagship smartphone, dubbed as iPhone 6, but speculations on its release date and specifications keep surfacing. Now, the latest we heard is that the device will be thinner than Samsung Galaxy S5, HTC One M8 and iPhone 5S.

iPhone 6 will sport a 4.7-inch display with rounded edges, a 67-millimeter-by-138-millimeter footprint, and an ultra-thin 6 millimeter cross-section, according to a report by UkrainianiPhone, which also provided a sketch of the purported smartphone.

The dimension of iPhone 6 is 138 x 67 x 6, according to the information given in the picture, which is much thinner than its counterparts from Samsung and HTC. The dimension of its predecessor, iPhone 5S is 123.8 x 58.6 x 7.6, while that of Samsung Galaxy S5 is 142 x 72.5 x 8.1, and HTC One M8 is 146.4 x 70.6 x 9.4.

This means iPhone 6 will be 1.6mm thinner than iPhone 5S, 2.1mm thinner than Galaxy S5 and 3.4mm thinner than HTC One M8.

The picture is in sync with earlier reports that Home button would house the scanner Touch ID and the power button on the top right side of the device.

Taiwan's Industrial and Commercial Times (Google translate) had earlier reported that the Cupertino giant might delay the release of the 5.5-inch variant of iPhone 6, as it is finding hard to find a battery slim enough to fit into the ultra-thin design of the device.

Considering the design of iPhone Air, the battery should be 2mm (0.08inch) or less, as against 2.8 to 2.9mm seen in usual smartphones, reported Industrial and Commercial Times, citing sources from the industry. It added that cutting down the size of the battery by one third could lead to a delay in the launch of the device, which could even be pushed to 2015.

It was reported that Apple might unveil two models of iPhone 6 at the upcoming WWDC event in June, but most media houses expect it to arrive only by September. A research note from UBS Managing Director Steve Milunovich (via Barron's) had earlier suggested that the 4.7-inch variant of iPhone 6 would be launched either in August or September, but the 5.5-inch model may or may not be released at the same time. Reuters and Nikkei also expect it to be unveiled in September.